Nitrostarch explosive and method of manufacturing same



UNITED STATES PATENT ornion WALTER 0. SNELLING AND WILLIAM R. LAMS, orALLENTOWN, PENNSYLVANIA,. ASSIGNORS, BY MESNE ASSIGNMENTS, To TROJANPOWDER COMPANY, or NEW YORK, N. Y., A CORPORATION or NEW YORK.

NITROSTARCI-I EXPLOSIVE AND METHOD OF MANUFACTURING SAME.

No Drawing,

, To all whom it may concern:

Be it known that We, WALTER O. SNELL- ING and WILLIAM R. LAMS, citizensof the United States, and residents of Allentown, Lehigh county,Pennsylvania, have invented certain Improvements in NitrostarchExplosives and Methods of Manufacturing Same, of Which the folloWing'isa specification.

Our invention relates to organic nitrate explosives and moreparticularly to nitrostarch explosives and their manufacture.

The problem of stabilizing nitro-starch in the preparation ofnitro-starch explosives presents difliculties, by reason of the factthat certain organic bodies well recognized as among the beststabilizing agents forv other nitro-explosives, have not been usablewith nitro-starch Without injurious effect upon the explosive.Nitro-starch is very readily colloided by a large number of organicsubstances, and such colloidization,

even when it is only superficial and does not extend materially into thesubstance of the nitro-starch granules, acts injurionsly upon thenitro-starch. The stability of nitrostarch Which is partly colloided isusually much less than is the corresponding stability of the uncolloidednitro-starch, and the sensitiveness to detonation is also infiuenced,colloided' nitro-starch being much We have discovered that the presenceof a heavy mineral oil, such as a medium or heavy lubricating oil, tendsto wholly prevent the colloiding action of basic stabilizing agents,without lessening in any way their stabilizlng properties. W e find thatSpecification of Letters Patent.

Patented Jan. 27, 1920.

Application filed June 22, 1918. Serial No. 241,354.

a heavy lubricating oil will dissolve from ten to thirty per cent. .ofits weight of dlphenylamin for example (the solvent action being greatlyfacilitated by Warming the oil somewhat), and that this mixture of o1land diphenylamm has stabilizing, but not colloidmg, properties. Itappears that the oil acts as a protection against colloidization of the'nitro-starch, the oil probably covering the surface of the nitro-starchgranules with a thin film, and this film of oil-saturated nitro-starchresisting the colloidizing action of the stabilizing agent.

In the practice of our invention, We use only small amounts of oil, andvery smallamounts .of the stabilizing agent. For ex.- ample, with afinished explosive containing 25% of nitro-starch, and .a total of about7 0% of sodium and ammonium nitrates, We may use from one-half of oneper cent. to a total of about 2% of oil, and this oil contains from 20%to 50% of its weight of the stabilizing agent, thus making the totalamount of stabilizing agent in the explosive vary from about one-tenthto three-tenths per cent.

As an illustration of a nitro-starch powder made up according to thepresent invention,

we give the following formula Nitrated starch 25.0% Ammonium nitrate.33. 0% Sodium nitrate 38.2% Charcoal 2.0% Sodium bicarbonate .5% Oil1.0% Diphenylamin .3% 4

In making such an explosive, the oil is preferably warmed to about (1.,and the proper amount'of diphenylamin is dissolved in it. This treated.oil is then preferably added to the mixture ofsodium and ammoniumnitrates, and this mixture is rolled or stirred until all of the grainsof the sodium and ammonium nitrate have been thoroughly coated with athin film of the treated oil. Preferably the sodium and ammoniumnitrates are quite warm before this mixing takes place, so as to preventtoo quick a chilling of the treated oil, which would precipitate some ofthe dissolved di-1' phenylamin. The other ingredients of the powder arethen mixed with the oil treated nitrates in any suitable manner. Ifdesired the nitrated starch may also be prelimmarily treated with thesolution of stabilizing agent in oil.

By dissolving the stabilizing agent in oil,

we obtain the further advantage of its uniform distribution. Most sodiumnitrate contains small amounts of iodids and iodates, and these twosubstances, by mutual reaction, set free minute amounts of iodin,

an adjacent nitro-starch granule and injuring it. By dissolvingdiphenylamin in oil,

- and then stirring the sodium and ammonium nitrate grains with a minuteamount of this treated oil, each particle of the nitrate becomes coatedwith a film of the diphenylamin-containing oil, and accordingly anytraces of iodin set free by reaction within that grain is caught on thesurface of the grain by the diphenylamin there present,

and is prevented from reaching the nitrostarch granules, although thesealsohave a minute film of the diphenylamin-containing 'oil on them, thusgiving a second point at which any traces of iodin may be caught.

While we prefer, in carrying out our invention, to dissolve thestabilizing agent in oil before incorporating said agent with otheringredients, other methodsof manufacture may be employed. For example,di-

phen'ylamin free from oil, can be added to the'heated sodium nitrate, orto the mixture of sodium and ammonium nitrates, and the heated mixturerolled or tumbled for some time at a temperature of preferably about 50C. or higher. Nitro-starch, previously mixed with a sufficient quantityof a heavy mineral oil to coat the nitro-starch particles with a thinfilm of said oil, is then thoroughly mixed with the treated inorganicnitrate, and the oil serves its function of protecting the nitro-sta'rchgrains fromthe colloiding effect of the diphenylamin.

By referring in our specification to diphefnylamin as a suitablestabilizing agent for the practice of our invention, we do not, in

its broader aspects, 'wish to be limited to that particular agent, asother stabilizing agents having colloiding properties may besuccessfully employed with nitrostarch by the method above outlined-suchfor exsolve said organic agent.

. and preventing colloidization of the nitrodissolving said agent in oiland thoroughly mixing therewith the nitro-starch to disseminate thestabilizing agent uniformly among the nitro-starch particles. I 2. Themethod ofi treating nitro-starch which consists in thoroughly mixing thesame with an organic colloiding agent in the presence of mineral oil insufiicient' quantity to provide the nitro-starch particles with acoating of said oil and thereby prevent col- 'loiding of thenitro-starch by the organic body.

3. The method of treating nitro-starch which consists in thoroughlymixing the same with an organic stabilizing agent in the presence of aheavy mineral oil in sulficient quantity to substantially; wholly dis-4. The method of treating nitro-starch which consists in acting thereonWith an organic body in the presence of an oil solvent thereof, therebystabilizing the nitro-starch starch by the organic body.

5. The method of treating nitro-starch which consists in acting thereonin the pres ence of mineral oil with an organic body containing an aminogroup.

6. The method of stabilizing nitro-starch which consists in actingthereon with diphenylamin in the presence of a heavy mineral oil.

7. The method of manufacturing nitrostarch explosives containing aninorganic nitrate which consists in thoroughly mixing said nitrate witha minute quantity of a mineral oil solution of an organic bodypossessing the property of stabilizing nitro-starch, and thenincorporating with the oil-treated nitrate the nitro-starch and otheringredientsof the explosive mixture.

8. The method of manufacturing nitrostarch explosives containing aninorganic nitrate which consists in thoroughly mixing saidnitrate with aminute quantity of a mineral oil solution of an organic body containingan amino group, and then incorporating with the oil-treated nitrate thenitro-starch and other ingredients of the eX- plosive mixture.

9. The method of manufacturing nitrostarch explosives containing aninorganic nitrate which consists in mixing said nitrate withdiphenylamin dissolved in a heavy mineral oil, and then incorporatingwith the treated nitrate the nitro-starch and other ingredients. 10. Themethod of manufacturing nitrostarch explosives containing an. inorganicnitrate which consists in mixing said nitrate with a minute quantity ofa mineral oil solu-' tion of an organic body possessing the prop-- ertyof stabilizing nitro-starch and then incorporating therewithnitrd-starch thoroughly mixed with a minu mineral'oil.

t quantity of 11. The method of manufacturing nitrostarch explosivescontaining an inorganic nitrate which consists in dissolvingdiphenylamin-in a heavy mineral oil at a temperature of about 80C'.,vthoroughly mixing with the inorganic nitrate a sufficient quantityof said solution to thoroughly coat the particles of said nitrate with-athin film of said oil,

and then incorporating with the oil-treated nitrate the nitro-starch andother ingredients of the explosive mixture.

12. A nitro-staLrch explosive containing an organic stabilizing agentand a mineral oil;-

13. A nitro-starch explosive containing diphenylamin and a mineral oil.

my in tenths 14:. A nitro-starch explosive containing diphenylamin and amineral oil,-the diphenylamin constituting from about onetenth to aboutthree-tenths per cent. by

weight of the entireexplosive mixture.

nitrates, approximately 70%; diphenylamin approximately .1% to .3%; andmmeral oil approximately .5% to 27 .17. An explosive mixture comprisingIntro-starch approximately 25% ammonium nitrate approximately 33%;sodium nitrate, approximately 38%; charcoal, approximately 2%; sodiumbicarbonate, approximately .5%; diphenylamin, approximately 7 3%;mineral oil, approximately 1%.

' WALT-ER o. SNELLING! WILLIAM R. LAMS.

